Final Fantasy Chronicles is a compilation of Square's role-playing video games Final Fantasy IV and Chrono Trigger: Final Fantasy IV introduced the Active Time Battle, a system designed by Hiroyuki Ito. It centers around the player inputting orders for the characters in "real time" during battles. Each character is balanced through certain strengths and weaknesses; for instance, a strong magic user may have low defense, while a physical fighter may have low agility. Chrono Trigger's gameplay deviates from traditional role-playing games in that, rather than random encounters, most enemies are openly visible on field maps or lie in wait to ambush the party. Contact with enemies on a field map initiates a battle that occurs directly on the field map itself rather than on a separate battle screen. Chrono Trigger uses an updated form of the Active Time Battle introduced in Final Fantasy IV, with additions such as "Techs" that rely on enemy positioning and abilities of characters. Other features are the employment of time travel and a "New Game Plus" option.